turbotim

Hi, I own a 85 zxt intercooled, piped, walbro fuelpump, adjustable regulator, set at 39psi when fully warm, greddy pressure sensor with greddy blue. I just started running 11psi and I decided to tune my airflow map by adding fuel from 8% at 2000 to 14% at 4000rpm. I go for a quarter mile run and as soon as I kick it in to second I go to give it almost full throttle and it spit and sputtered and afr goes lean. So I go back to my airflow map and change everything back to 0, and now I do a run and she doesn't sputter the fuel mixes with the air right and runs like a dream. My afr go to 10 when I hit it and feel the most boost then it raises slowly to 13 if I keep going for it but I think maybe boost is tapering off! Why did the car run better with 0 at 11 psi can Nissan still pump the fuel in to match the 11 psi? Is the better way to tune is to turn up your fpr to get more fuel and then just fine tune the map from there or? By the way if I run any more boost I have 460cc laying around. But first I want to understand the right way to run 11 psi on a z31.

turbotim

Turned the boost back down to 9 and she runs great can't get a sputter or lean spot! So I think the problem is number1, I am pushing my stock injectors to hard maybe! Number 2 im trying to only adjust airflow map and I think that's mostly for fine tuning and idle or taking fuel away. In all reality I think I need to put in the bigger injectors, wire them, then use my additional injection map to add fuel only. Should work a lot better then. I just thought the z31 could run 11 psi safely on stock injectors!

turbotim

Fixed, was the 25+ year old injectors, they were not good any more especially for 10psi!

rogerz

you are blowing smoke out your ear. My 85 and my 86 ran just fine with 10psi boost using the original injectors and no fancy intercooler or fuel pump. you modified so much you don't know what is going on anymore.

turbotim

My car runs perfect now, anytime u wanna race let me know. I don't know if u understand English, but in my car at 10psi, my injectors were failing, cause they are old. They were no good. And if I don't know whats going on. How come I am running 13psi on 460 rx 7 injectors tuning by map sensor. Perfect afr everywhere. My car is my dream come true. I am very proud of what I have done. If u would like, I will take pics and give u the whole download on my car, if its hard for u to wrap you're head around. And putting a fancy intercooler and fuel pump on you're car will not make it run any differently then before!

NismoPick

If they were plugged up / gunked up or otherwise toast, then yes a new set will make a difference. I've been there, done that.

BTW, if you are [you're] going to accuse someone of not understanding English, you should probably know how to spell and use proper spelling and grammar yourself.

Food for thought...

u = you
you're = you are [i.e. "You're amazing!"]
your = possessive [i.e. "Your dog is amazing!"]

turbotim

I can not say nothing about that, you are right Nismopick! I'm not to good at English or grammer! Good eye!